Research on the all-position pipeline automatic welding carriage

In order to explore deep water oil and gas fields in South China Sea area, an all-position automatic pipeline welding carriage was developed, applied in sub-sea pipeline laying. The welding carriage is specially designed for offshore application, so it is compact and lightweight. The control system of the automatic welding is constructed on the CANOpen bus and Ethernet technologies, so the pipeline welding process can be monitored remotely. A master-slave CAN-bus network control welding system is constructed, which is composed of CAN-bus master and welding power source based on CANopen communication. This system satisfies the requirements of all-position welding process that welding system can weld with mated welding parameters at any position. The accuracy of two-axle synchronous movement and the operation stability of welding bug are ensured by using the current follower arithmetic.